Most systems used for locating objects use expensive infrastructure or global positioning system (GPS), to determine the position of the object. However, such locating systems are characterized by shortcomings associated with power requirements and expensive infrastructure, and operating environment limitations in the case of GPS. As a result, such conventional methods and systems are often not suitable for finding, tracking and locating people and objects in many types of environments.
Typical radio frequency (RF) systems have a fixed infrastructure and disadvantages for tracking continuous and/or combined movement of objects without the requirements of setting up fixed RF reference points, antenna size, range and RF wavelength. Systems having fixed signals require additional devices and installation costs; and these systems have disadvantages of signal interference and degradation that further limit their performance due to low power and compactness of RF systems used to search, locate and track objects. As a result, there is a need in the art for reducing fixed reference points, which also has advantages of enabling a system to locate objects utilizing the continuous and/or combined movement of both the objects and Master Units.
As a result, such conventional methods and conventional RF systems are not suitable for finding, tracking and locating objects in an environment with no fixed infrastructure, when only two devices (Master and target) are present in the environment, or when a signal, such as a GPS signal, is unable to be received, for example, inside a mall, urban canyons, etc. GPS may not be available in such locations because the GPS receiver device needs to receive signals from at least three satellites or reference points (i.e., the GPS receiver has to be in line of sight of at least three satellites), in order to determine the location of the person or object being tracked. Each reference point is gathered by the UPS receiver and then needs to be processed by the GPS receiver.